Swedish dialects in Ostrobothnia

Ostrobothnian Swedish (Swedish: österbottniska) is a variety of Finland-Swedish, spoken in Finland. Outside the autonomous island province of Åland, which is officially monolingually Swedish, Ostrobothnia is the only region of Finland where Swedish-speakers are the majority (51%). Ostrobothnian Swedish-speakers are traditionally farmers, and as such, isolation of the communities produces strong dialectal variations.

One famous Swedish dialect in Ostrobothnia is the Närpes dialect, whose mutual intelligibility with other forms of Swedish is questionable. Finland-Swedes have difficulties with understanding the Närpes dialect, and it is almost unintelligible to anyone else, so speakers of the Närpes dialect have to learn standard Swedish, as well.

Some of the most archaic Nordic dialects in Mainland Scandinavia are found in Ostrobothnia, especially regarding pronunciation. The abovementioned Närpes dialect is in syntax, grammar and vocabulary fairly close to Icelandic, hence the difficulties in understanding. They also share many common features with the Westrobothnian dialects spoken on the other side of Kvarken, in parts of Westrobothnia and Norrbotten.

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Wikipedia